mineral

Tumbled quartz (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent white to pale peach with a waxy-to-vitreous luster. It has a hexagonal crystal structure but commonly occurs massive, with no cleavage and conchoidal fracture; coloration may reflect iron staining or surface treatment.

Identified August 15, 2026More mineral →

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Physical properties

Formation & geological history

Quartz crystallizes from silica-rich igneous and hydrothermal fluids, or precipitates in veins and cavities; most specimens formed over broad Precambrian-to-Phanerozoic intervals. This piece appears rounded and polished by tumbling, possibly with minor iron-oxide staining.

Uses & applications

Used in glass, ceramics, electronics, abrasives, engineered stone, and jewelry. As a small tumbled specimen, its primary value is decorative or educational.

Geological facts

Quartz is one of Earth’s most abundant minerals and is the defining mineral of Mohs hardness 7. Milky appearance results from microscopic fluid inclusions, fractures, or inclusions scattering light.

Field identification & locations

Identify it by its hardness, glassy fracture, lack of cleavage, and inability to scratch it with a steel knife while scratching ordinary glass. Common sources include Brazil, Madagascar, the United States, and worldwide quartz veins.